Network issue with one remote site while transferring files to another.

Diagram: https://imgur.com/rdK21wO

While transferring large files to Site C from Site A connection to Site B appears to reach saturation, causing lost connections and transmission errors. This only occurs when transferring to or from Site C. Transferring files inside Site A has no effect on the connection to or from site B. Site A is the default route for both B & C.

Both sites are connected to Site A through the Core Switch.

• Site B via 10Mb Metro-E, Using EIGRP with a trunked vlan interface(non-standard Management network).

• Site C via Dark Fiber trunked on the same network management Vlan, as all other switches on Site A.

Site C shares no networks or vlans with Site B, and Site C is not shared with site B via EIGRP.